A: First things first; is the installation of the AHU a replacement or a completely new installation? If a replacement, it can be installed “like for like”. If a new installation, are the trusses capable of supporting the additional dead loads? An evaluation of the existing truss system by a registered design professional would be necessary. See FBC, Residential Code, Section R802.10. regarding engineered roof trusses.

A: You are being told that most likely due to the ASTM provisions. FBC, Residential, Section R703.7, Exterior Plaster references ASTM C926 and ASTM C1063 and the provisions of “this code”. While Section R703.7.1 limits fastener spacing to a maximum of 6” on center, consider that ASTM C1063 was developed for use over open framing – i.e. shear panels provided only where necessary. As such, the standard requires the wire lath to be tied in between the framing members and the end laps to be laced with wire.

A: Numerous sections of FBC Ch. 1, Scope and Administration are intentionally marked as “Reserved” to allow each jurisdiction to amend each such marked section as applicable for that particular jurisdiction.

A: A Corridor and an Exit Passageway are both defined terms:

CORRIDOR. An enclosed exit access component that defines and provides a path of egress travel.

EXIT PASSAGEWAY. An exit component that is separated from other interior spaces of a building or structure by fire resistance-rated construction and opening protectives, and provides for a protected path of egress travel in a horizontal direction to an exit or to the exit discharge.

While a corridor and an exit passageway are both components of the means of egress system, a corridor is not necessarily required to be of fire resistant rated construction while an exit passageway is, by definition, always rated. By definition, an exit passageway “provides a protected path of egress travel in a horizontal direction to an exit or to the exit discharge”.